/*! Copyright (c) 2011 Brandon Aaron (http://brandonaaron.net)
 * Licensed under the MIT License (LICENSE.txt).
 *
 * Thanks to: http://adomas.org/javascript-mouse-wheel/ for some pointers.
 * Thanks to: Mathias Bank(http://www.mathias-bank.de) for a scope bug fix.
 * Thanks to: Seamus Leahy for adding deltaX and deltaY
 *
 * Version: 3.0.6
 *
 * Requires: 1.2.2+
 */

(function($) {

	var types = ['DOMMouseScroll', 'mousewheel'];

	if($.event.fixHooks) {
		for(var i = types.length; i; ) {
			$.event.fixHooks[types[--i]] = $.event.mouseHooks;
		}
	}

	$.event.special.mousewheel = {
		setup : function() {
			if(this.addEventListener) {
				for(var i = types.length; i; ) {
					this.addEventListener(types[--i], handler, false);
				}
			} else {
				this.onmousewheel = handler;
			}
		},
		teardown : function() {
			if(this.removeEventListener) {
				for(var i = types.length; i; ) {
					this.removeEventListener(types[--i], handler, false);
				}
			} else {
				this.onmousewheel = null;
			}
		}
	};

	$.fn.extend({
		mousewheel : function(fn) {
			return fn ? this.bind("mousewheel", fn) : this.trigger("mousewheel");
		},
		unmousewheel : function(fn) {
			return this.unbind("mousewheel", fn);
		}
	});

	function handler(event) {
		var orgEvent = event || window.event, args = [].slice.call(arguments, 1), delta = 0, returnValue = true, deltaX = 0, deltaY = 0;
		event = $.event.fix(orgEvent);
		event.type = "mousewheel";

		// Old school scrollwheel delta
		if(orgEvent.wheelDelta) {
			delta = orgEvent.wheelDelta / 120;
		}
		if(orgEvent.detail) {
			delta = -orgEvent.detail / 3;
		}

		// New school multidimensional scroll (touchpads) deltas
		deltaY = delta;

		// Gecko
		if(orgEvent.axis !== undefined && orgEvent.axis === orgEvent.HORIZONTAL_AXIS) {
			deltaY = 0;
			deltaX = -1 * delta;
		}

		// Webkit
		if(orgEvent.wheelDeltaY !== undefined) {
			deltaY = orgEvent.wheelDeltaY / 120;
		}
		if(orgEvent.wheelDeltaX !== undefined) {
			deltaX = -1 * orgEvent.wheelDeltaX / 120;
		}

		// Add event and delta to the front of the arguments
		args.unshift(event, delta, deltaX, deltaY);

		return ($.event.dispatch || $.event.handle).apply(this, args);
	}

})(jQuery);